The present invention relates to the field of expansion mechanisms for a palmtop computer. More particularly, the present invention relates to a mechanism for sharing memory access with an accessory such as a palmtop sled based accessory.
As the components required to build a computer system have reduced in size, new categories of computer systems have emerged. One of the new categories of computer systems is the xe2x80x9cpalmtopxe2x80x9d computer system. A palmtop computer system is a computer that is small enough to be held in the hand of a user and can be xe2x80x9cpalm-sized.xe2x80x9d Most palmtop computer systems are used to implement various Personal Information Management (PIM) applications such as an address book, a daily organizer and electronic notepads, to name a few.
While these palm sized computers (xe2x80x9cpalmtopxe2x80x9d computers) have dramatically reduced size when compared to a desktop or notebook computer, the user would like to be able to perform many of the same types of functions performed using physically larger and more powerful computers. Such functions often require substantial amounts of memory and/or circuitry that is not generally incorporated within a palmtop computer. An example of such a function is that of an MP3 music player. It is conceivable to embed such a player within a so-called xe2x80x9csledxe2x80x9d device that couples to the palmtop computer. Unfortunately, such devices are taxing on the processing power of a palmtop computer if the music is stored either on the palmtop computer itself or on a storage device associated with the palmtop computer. In order to access such storage for real time audio playback using an MP3 player, the data stored in the memory device of a conventional palmtop must be converted to a serial format to be transferred through the processor to the serial connector of the palmtop before being played back by such a sled based MP3 player. This is cumbersome and taxing on battery life and processing power of the palmtop computer. Nonetheless, such an arrangement would have advantages since the MP3 player or other sled-based device could theoretically use the palmtop computer as a user interface and could use an existing memory interface to store music or other relevant data.
Unfortunately, the above listed drawbacks may be prohibitive in implementing such an arrangement. Thus, the cost of such sled accessories may suffer by needing to supply an additional connector to support its own memory for storing data (e.g. MP3 music) or personality programs.
Accordingly, what is needed is an arrangement to permit a sled-based device to directly access a palmtop computer""s memory.
In accordance with one embodiment of the invention, a palmtop computer utilizes SD memory modules or other types of memory modules to provide expansion memory. The expansion memory module plugs in to the palmtop computer via an external slot or compartment that is easily accessed by the user. This provides additional memory to the palmtop computer. To facilitate use of expansion devices such as sled or cradle based devices, a connector is provided on the palmtop computer that not only includes conventional power, ground and serial communication terminals, but also provides direct access to the memory module for use by the expansion device. This provides the advantage that the sled or cradle based device can directly access the palmtop computer""s memory without using the palmtop computer""s processing resources.
A method of expanding capabilities of a palmtop computer with a memory expansion module in accordance with an embodiment of the present invention includes: coupling the memory expansion module to a processor within the palmtop computer; coupling the memory module to an expansion port of the palmtop computer; and coupling a sled device to the palmtop computer, so that the sled device is coupled directly to the memory expansion module and to a communication port of the palmtop computer.
A palmtop computer having enhanced expansion consistent with embodiments of the present invention includes a central processor connected to a bus. An expansion memory is operatively coupled to the bus to provide the central processor with access to the expansion memory. A communication interface is operatively coupled to the bus to provide the central processor with communication with devices outside the palmtop computer. A connector, operatively coupled to communication interface and to the expansion memory, permits an external device to communicate with the central processor via the communication interface and to permit the external device to directly access the expansion memory module.
An expansion device for a palmtop computer consistent with the present invention, wherein the palmtop computer has a central processor, an expansion memory, a communication interface and a palmtop-side connector, the palmtop-side connector being operatively coupled to the communication interface and to the expansion memory, includes an expansion device-side connector suitable for mating with the palmtop-side connector. An expansion device-side communication interface is connected to the expansion device-side connector for communicating with the communication interface of the palmtop computer. A memory interface is connected to the expansion device-side connector for directly accessing the expansion memory of the palmtop computer.
The above summaries are intended to illustrate exemplary embodiments of the invention, which will be best understood in conjunction with the detailed description to follow, and are not intended to limit the scope of the appended claims.